<PRE><B>Question 719614</B>
Determine whether the lines through the given pairs of points are parallel. A (2, - 3), B (- 2, - 11) and C (1, 2), D (- 1, 6)
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Find the slopes.  If, and only if, the slopes are equal, they&#39;re parallel.
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For AB:  A (2,- 3), B (- 2,- 11)
slope m = diffy/diffx
m = -8/(-4) = 2
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Find the slope of CD, compare them.
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PS  Don&#39;t put a space after the comma in the points.
(1,2) not (1, 2)
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